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Telling Lies to the Police: Part 2

Updated: May 11, 2022

False confessions

Part 2: Ireland

-And you stabbed her?


-And you dragged her back into the room?


-Is that right?


-Did you put her on the bed?


-Right. Where was she?

-I left her on the floor.

-Just standing on the floor?


-Or lying on the floor?

-Lying on the floor.

- Dean Lyons interview.

Bridewell Garda Station, 26 July, 1997.

Part 1: The Trap

ON 7 MARCH 1997 two elderly women, Sylvia Shields and Mary Callinan, were found dead in their home. They were living in sheltered psychiatric accommodation at 1 Orchard View, Grangegorman, Dublin. Their throats had been cut and their bodies mutilated.

The Gardai (Irish Police) interviewed about 250 suspects. But four months after the murders they had no suspects.

On 26 July 1997 the Gardai asked Dean Lyons, a petty criminal and heroin user to come to the Bridewell Garda Station to make a statement. It wasn’t particularly relevant; dozens of other transient individuals had been asked to do the same thing. Lyons was happy to assist the Gardai. He was not a suspect. Routine questions were put to Lyons just like all the others before him.

As the interview was concluding the Detective asked Lyons a hypothetical question. It was the sort of hypothetical question detectives across the world often ask suspects when they have no evidence against them.

As a detective you ask it just to gauge a response, to see what the other person says, to see if there’s a flicker in their eye.

But the question was a trap – a trap baited with a fixed view of human behaviour. Though the question had been designed to trick Lyons, the detective had unwittingly laid the trap for himself.

Lyons was asked how he might react if his fingerprints were located at the scene of the murders. This question is significant. It is worth reading again. It is a psychological ploy designed to sow doubt in the mind of the person being questioned.

The theory is that by hinting that maybe the Gardai have found a person’s fingerprints at the scene that’ll cause them to begin to doubt themselves. Could my prints be there somehow?

Was I there once and maybe forgot it? If I say I wasn’t there and they find out I was at one time, I’ll be in even bigger trouble…

Still, most people would brush this question aside. Most people with a degree of mental strength would dismiss the idea that their fingerprints might be found at the scene of a murder. This is murder after all.

But Dean Lyons wasn’t most people.

Gardaí would later say that Lyons became very nervous and suddenly began to shake. He was asked whether there was something bothering him and he began to cry. He said that “he had killed the two old ladies and he was sorry”.

He kept saying that he had killed them and kept asking for forgiveness. He was arrested.

The Gardai needed an arrest, they were desperate

for an arrest and when Dean Lyons suddenly

admitted to the murders, the flying train began to

pick up speed. But it would shortly derail,

and in spectacular fashion

WHEN A SERIOUS CRIME like murder occurs, pressure builds very quickly. Firstly, the media descends on the area where the murder occurred, all the more so if the deceased is not in any way connected with criminality.

When this happens, media interest hits fever-pitch. Very quickly a siege-mentality sets in at the Garda station leading the investigation. Nobody talks to anyone, understand?

With media pressure from outside comes pressure from above. Police Headquarters are ringing with urgent questions. Representatives from HQ have been dispatched to your station.

They have a script for you to read to journalists. Read it and don't dare deviate from it.

The investigation has now boarded a train.

HQ have questions and you had better be able to answer them or at least give the impression that you know what you’re doing. The media and public expect arrests quickly.

So does HQ.

The pressure on the lead investigators is suddenly intense. They begin imagining their future should they bring this murder case to a successful conclusion. Promotions will naturally follow.

Promotions mean enhanced status, enhanced salaries, a chance to be someone, to be seated at the top table at the next Divisional Ball.

But if you cant solve the case deep worries start to claw at you. You imagine a different scenario, one where HQ is evaluating you, talking about you, and not in good terms.

“If you’re not making arrests, then maybe you’re not very good at your job? Do we have to get someone down there who knows what they’re doing?”

The Gardai needed an arrest, they were desperate for an arrest and when Dean Lyons suddenly admitted to the murders, they were elated. But the Lyons’ admission was a trap, a deadly trap made even more deadly because Lyons was a criminal and a drug addict.

But it was possible now to see the outline of the trap that Lyons had laid. It wasn’t even necessary to look beneath the surface to see the jaws.

The reality was visible right on the surface.

DEAN LYONS WAS A FANTASCIST and an attention-seeker. He was 24 and of below average intelligence. He was addicted to heroin and was homeless. He had a criminal record and had been convicted of burglary and syringe attacks. He told lies frequently.

Some of his lies had a disturbing edge.

His father had once suffered a heart attack and one day at school Dean feigned a heart attack. His teachers would later recall just how vivid his performance had been and how frighteningly realistic it was.

On another occasion he fooled his parents into believing that he had suffered a serious spinal injury. His parents brought him to hospital and Dean laughingly hopped off the hospital trolley.

His father had once suffered a heart attack

and one day at school Dean feigned a heart attack.

His teachers would later recall just how vivid

his performance had been

and how frighteningly realistic it was

He often admitted to things he had not done, especially if this gained him favour with those around him. One day at home his father questioned his children as to which of them had improperly lit a fire in the kitchen.

Dean admitted to this immediately. His father only discovered one year later that Dean had had nothing to do with it.

When a window was broken one day at school, Dean admitted to it right away. It was later discovered that he had almost certainly nothing to do with it.

On another occasion when his friend was arrested for shoplifting Dean took the blame. He was only ruled out as a suspect when CCTV was later viewed.

"I see what I want to see..."

WHEN INVESTIGATIONS GO WRONG two fatal errors are usually prevalent: tunnel vision and confirmation bias.

Tunnel vision is a narrow belief in a set theory, in a set view, that a suspect is guilty, no matter what the evidence might say. This usually takes the form of focusing on a suspect, to the exclusion of all other potential suspects.

Confirmation bias is the tendency to search for, and favour information, that confirms or supports your prior beliefs or values. You only believe and accept what corresponds to your view.

Everything else is dismissed.

Lyons’ confession was a voluntary false confession, in that he confessed -without oppressive tactics being employed- to something he hadn’t done.

Where false confessions have occurred, they have always followed a particular road. It is a dreary road that leads through a dense forest. Shadows abound.

The investigation had now begun to warp. Instead of checking to see if Lyons’ story made any sense, the Gardai began to take Lyons’ at face value and to focus on substantiating his stories and their preconceived notion that Lyons was the murderer.

Instead of checking to see if Lyons’ story

made any sense, the investigation team

became gripped by a sort of frenzy

Elation descended. Lyons was now the chief suspect even though he hadn’t told them anything they hadn’t already known beforehand.

Worrying flaws were ignored as long as they accorded with the dominant investigative theory. When the detectives discovered that Lyons had lied to them about having a pregnant girlfriend, this did not cause them to question his reliability. Instead they rationalised the lie.

Prior to arresting Dean Lyons, the Gardai, with the assistance of the Home Office in Britain, had recruited experienced criminal profilers. The profile they created suggested that the offender likely had violent fantasies in relation to the violent overpowering of women and “was unlikely to have had any sexual experience in the past”.

Instead of being concerned that Lyons had told them a blatant lie about a fictitious pregnant girlfriend, confirmation bias took over. The lie could be ignored, the Gardai reasoned, because it meant that Lyons fit the description that the profilers had created of a sexually inexperienced culprit.

The investigation was now deep among the gloomy trees of the forest. The path was narrow and lonely.

They kept hearing the echo of their own voices.

The deadly twin combination of tunnel vision and confirmation bias had now firmly taken hold.

It was soon followed by another serious flaw.

“Look, he has told it on tape, he has told it off tape, he has told it to his mother, what more do you want?”

-Remark attributed to Detective Chief Superintendent Camon

DEAN LYONS HAD NOTHING TO DO with the murders. He had made the whole thing up. But his lies had convinced even seasoned investigators who believed him, or wanted to believe him. To bolster their views the Gardai began asking leading questions virtually from the beginning.

Leading questions are banned in courtrooms across the world. They are outlawed because they are designed to produce a desired answer, not the truth. They are not evidence. But they are permitted in police interviews.

The Gardai frequently resort to them during questioning for the same reasons that they are banned in courts: they are subjective, not objective. They are easy to frame. The questions being asked are suggestive of the answer being sought.

The Gardai now began to frame almost all questions to Dean Lyons in this way. They did so because the investigation, as far as they were concerned, was over. All they needed was for Lyons to neatly give them the answers they wanted and to sign his name to it.

But the Gardai had badly underestimated the person they were speaking to.

Lyons wasn’t just an accomplished liar, he was a person who was eager to please. It was in his nature. It was also disastrous from the investigation’s perspective: here was a man willing to admit to virtually anything, even murder.

Lyons quickly began to interpret subtle cues from the demeanour and tone of voice of the Gardai. Instinctively he knew what they wanted, and he began to tailor his answers to accommodate these wants.

He began to “provide” details of the crime, as well as the crime scene. But the details which he provided were given to him by the Gardai and using his fertile imagination Dean Lyons began to anticipate and repeat back to them what they wanted to hear e.g.

-And you stabbed her?


-And you dragged her back into the room?”


-Is that right?


-Did you put her on the bed?


-Right. Where was she?

-I left her on the floor.

-Just standing on the floor?


-Or lying on the floor?

-Lying on the floor.

In this instance Lyons was being “fed” not only the Gardai’s own working assumption of the crime scene but was also interpreting from some of the questions asked (“or lying on the floor?”) that his answers were incorrect.

Here Lyons was initially saying that he left the deceased “standing on the floor” but when offered a new alternative (“lying on the floor”) he immediately opted for that, a shift that was in keeping with his personality of trying to please other people and his skill, honed over many years, of understanding what the other person wanted.

But the difference between placing a body standing up or lying down was enormous and should have immediately rang alarm bells among the investigating Gardai. It did not.

The investigation moved deeper into the forest. The trees seemed to close behind them as they passed. Still, they could see light, or what they thought was light, in the distance, leading them home. It seemed within reach.

They moved towards it, the true believers of the investigation team along with the muttering stragglers behind.

But the light wasn’t getting brighter, it was growing dimmer.


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